JP3061098B2 - Optical disk, optical disk reproducing apparatus, and optical disk recording method - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an optical disk for preventing unauthorized copying on a CD-ROM or the like on which information such as a TV game is recorded, and an optical disk reproducing apparatus for checking the disk to determine unauthorized copying. And an optical disk recording method for recording information on the optical disk .

[0002]

2. Description of the Related Art When music, images, characters, data, and the like are represented as digital information signals, the information is copied (duplicated) in comparison with the case where they are represented as analog information signals. ), There is no information deterioration in transmission characteristics. For this reason, it is currently a serious problem in terms of copyright, and it is required to prohibit or restrict the copying of digital information signals as they are.

[0003] For example, CD-ROMs and the like
60 "and the like. When copy protection is performed in accordance with this standard, a copy protection code must be recorded on a disc in advance. And if it has this code, it is a legitimate disk,
If there is no code, it is determined that the disk is an illegal copy disk, and measures such as stopping reproduction thereof are taken. CD-ROMs currently being commercialized and those to be commercialized in the future
It is thought that the one that complies with this standard will become mainstream.

However, in such a copy protection method, a copy disk that can be easily accepted as a regular disk can be easily manufactured by using a copy machine that copies the entire recording data of the disk. For this reason, discs with weak copy protection are circulated, leading to illegal copying.

[0005] Therefore, a unique standard different from the above-mentioned disc standard has been created, and a standard CD such as “ISO9660” has been developed.
-A method of applying copy protection so that it cannot be read by software that reads ROM can be considered. However, even if such a method is used, any disk is copied by using a copying machine that reads data from a disk in physical frame units and copies the data to a CD-WO or the like.

In the MD, a copy protection method called SCMS (Serial Copy Management System) is adopted. This SCMS protects a part of the digital signal recorded on the MD.
A system that attempts to prevent more than one digital copy by referring to a code. That is, M
A protect code is written in the data of the TOC area of D. (1) If the protect code is not protected, the MD can be copied. If the copy is made, the TOC area of the copy destination MD is stored in the TOC area of the copy destination MD. Protected protection code is written. (2) If the protected code is protected, the MD is a copied MD and cannot be copied again. In this way, copying by a digital signal more than once is prevented.

As described above, in the SCMS method, a protect code is written in information recorded on a disk, and the apparatus determines whether copying is possible or not by referring to the protect code.

However, when information recorded on a disk is directly read as a recording signal and recorded on another disk, the entire protection code is copied irrespective of the contents of the protection code. become. For this reason, copying can be performed any number of times, and illegal copying in terms of copyright cannot be prevented.

In a commercially available IC for a CD player or a CD-ROM drive, a tracking error is monitored. If the error exceeds a certain level, it is determined that an impact has occurred and the servo gain is determined. (For example, IC “TC9236AF” manufactured by Toshiba Corporation). Alternatively, the amount of reflected light from the disk is monitored, and if the amount of light decreases or rises to a certain extent and changes at or above the slew rate, it is determined that the disk is dirty or defective, and the PLL is held or muted. (For example, IC “AN8803 manufactured by Matsushita Corporation”).
SB ").

Therefore, if such a function is effectively used, copy protection can be realized by using a conventional IC without special circuit design or the like. The present invention focuses on these points, and prevents the information for protection contained in the recording signal from being read out by simply reproducing the recording signal recorded on the disk in the conventional manner. by detecting the information easily and accurately, the light can be favorably prevented illegal disc copy
Disc, optical disc playback device, and optical disc recording method
Its purpose is to provide the law .

[0011]

In order to achieve the above object, an optical disk according to the present invention is an optical disk in which each pit is formed symmetrically with respect to the track center and provided with a large number of pit rows. A unique pit row having a shape or arrangement different from that of the pits is included in relation to a data block of a modulation signal recorded as a normal pit row.

The singular pit row includes an arrangement in which a wobble signal is obtained from a tracking error signal, an arrangement in which the symmetry of an RF signal fluctuates, an arrangement in which a light amount signal fluctuates,
Either of the arrangements for obtaining a burst wobble signal. Or, in addition, the arrangement is intermittent.

The optical disk checking apparatus of the present invention comprises:
Reproducing means for reproducing an area in which the specific pit string is arranged; detecting means for detecting the presence or absence of the specific pit string from the reproduction result, and discriminating whether the disc is a regular disc or an illegal copy disc based on the result; It is characterized by having.

A recording apparatus for an optical disk according to the present invention comprises: laser light source means for generating and outputting laser light; signal conversion means for converting digital data into a modulation signal; and laser light emitted from the laser light source means having an intensity corresponding to the modulation signal. A laser light modulating means for modulating; a gate generating means for generating a gate signal synchronized with a data block unit of a modulation signal; and at least one of beam deflection, duty correction, and laser light modulation corresponding to the singular pit row, Laser light changing means for giving a laser light in synchronization with a gate signal; Laser light modulating means and laser light irradiation for irradiating the laser light modulated and changed by the laser light changing means onto an optical disc to form a pit row Means;

The main aspects of the present invention are as follows. (1) An optical disc in which each pit constituting the singular pit row is arranged on a center line wobbled in a radial direction with a maximum amplitude smaller than a track pitch. (2) The wobbling frequency of the center line is higher than the tracking servo band, and when reproduced by an optical pickup having a tracking side beam, a reproduced signal component included in a tracking error signal is minimized; An optical disc having a frequency at which the wobbling signal carrier is maximized.

(3) An optical disc in which the above-mentioned unique pit row is arranged on a portion of the disc where a reproduction signal component included in a tracking error signal is reduced. (4) An optical disc in which the pits forming the singular pit row are arranged with a duty different from the duty of the pits forming the normal pit row. (5) An optical disc in which the pits forming the singular pit row are arranged with different radial widths from the pits forming the normal pit row.

(6) A decoding device for reading an information recording section of an optical disk and decoding the contents of a data block of the disk, a detecting device for detecting whether a servo signal or a data signal obtained from the disk is normal or abnormal, and a decoding device And a device for detecting whether the signal from the device and the output from the detecting device are associated with each other at the timing of a predetermined certain rule, and whether the specific signal previously recorded on the disc is detected by the detection signal of this device. An optical disc check device comprising a function of discriminating, on a volume basis, an optical disc composed of only regular pits and an optical disc in which a pre-recorded unique pit is detected.

(7) In the device of (6), a tracking error signal detecting device, a device for detecting whether the signal is substantially constant or changing in a burst, and a unique device provided on a disk read by the signal. An optical disk check device including a device for determining whether a pit is detected and controlling a subsequent reproduction operation, and having a function of discriminating a disk by a volume unit depending on the presence or absence of a unique pit in the optical disk.

(8) The pickup of the device of (6) is 3
An apparatus that uses the beam method and detects whether the tracking error signal is substantially constant or changes in a burst shape is configured by a band-pass filter circuit, a rectifier circuit, and a comparator circuit. An optical disc checking device wherein the center frequency of the filter circuit is set to a frequency at which a burst signal appearing in a tracking error signal is maximized and a leakage of a data signal appearing in the tracking error signal is minimized.

(9) In the device of (6), a device for detecting the vertical symmetry of an RF signal in a device for converting RF data from an analog signal to a digital signal, and an apparatus for converting the RF signal in accordance with the vertical symmetry. In addition to the device for varying the slice level, a device for comparing whether the variation of the slice level is out of the reference or within the reference, and determining whether or not the specific pit is detected in the read disk based on a signal from this device. An optical disk checking device including a device and having a function of discriminating a disk by a volume unit depending on the presence or absence of a unique pit in the optical disk.

(10) In the device of (6), a device for irradiating a laser beam to an information recording portion of an optical disk and outputting a signal of the amount of reflected light from the disk is provided. An optical disc checking device having a function of comparing a device to be compared and a function of judging whether or not a specific pit is detected from a read disk based on a signal from the device, and discriminating the disk in units of volume according to the presence or absence of abnormal pits.

(11) In the apparatus of (6), a predetermined position in a predetermined data block of the disk is recognized, and a tracking error signal which changes in a burst at a certain regular timing according to the position is detected in synchronization. Or whether a specific pit is detected in the disk by determining whether a change in the slice level according to the vertical symmetry of the RF signal is detected in synchronization or a change in the reflected light amount of the disk is detected in synchronization. An optical disk check device having a function of determining whether a disk is a discrimination unit by volume.

(12) In the apparatus of (6), a predetermined position in a predetermined data block of the disk is synchronized with a tracking error signal that changes in a burst form, and is intermittently detected at each predetermined position. Or, a predetermined position in a predetermined data block and a slice level change corresponding to the vertical symmetry of the data signal are synchronously and intermittently detected at each predetermined position, or a predetermined position in a predetermined data block and a disk are detected. It utilizes the fact that fluctuations in the amount of reflected light are detected synchronously and intermittently at each predetermined position, and as a result of reading a certain number of data blocks, a tracking error signal or slice level signal or disk reflected light amount If the number of times that signal fluctuations are recognized as being detected is equal to or more than a predetermined number and the number of times that signal fluctuations are recognized as not being detected is equal to or more than a predetermined number, the above-described operation is correctly performed Signal is determined to have be read, an optical disc checking device having a function of discriminating the disk and volume units unreadable.

(13) In the apparatus of the above (6), a predetermined data block address for judging the type of the disk based on whether or not a specific pit is detected in the information pits in the disk is stored in advance. At the time of setting, the data block area of the address is read, and it is determined whether a fluctuation of the burst tracking error signal, the slice level signal or the disk reflected light amount signal is detected at the address, and it is determined whether or not the disk has abnormal pits detected. Optical disc checking device with the function of discriminating discs by volume.

(14) In the apparatus of the above (6), a predetermined address in which a data block address for judging the type of the disk based on whether or not a specific pit is detected in the information pits in the disk is recorded as a table. Is stored in advance, the area of the address is read when the disk is set and recognized as a table, the area of the data block address described in the table is read, and a burst tracking error signal or a slice level signal or An optical disk check device having a function of verifying whether a change in a disk reflected light signal has been detected, determining whether or not an abnormal pit has been detected, and discriminating the disk in volume units.

(15) a laser light source, means for converting digital data into a modulation signal, means for intensity-modulating laser light emitted from the laser light source in accordance with the modulation signal, and converting the laser light into recording laser light; An objective lens for irradiating a recording laser beam onto the optical disc to form a pit row, a means for generating a gate signal synchronized with a data block unit of the modulation signal, and the singular pit row synchronized with the gate signal. An information recording device comprising: a generating unit.

(16) a laser light source, a means for converting digital data into a modulation signal, a means for intensity-modulating the laser light emitted from the laser light source in accordance with the modulation signal, and converting the laser light into a recording laser light; An objective lens for irradiating a recording laser beam onto an optical disc to form a pit row; a means for generating a gate signal synchronized with a data block unit of the modulation signal; and generating a wobble signal in synchronization with the gate signal An information recording apparatus comprising: means for deflecting the recording laser beam in a radial direction on a disk in response to a wobble signal.

(17) a laser light source, means for converting digital data into a modulation signal, means for intensity-modulating laser light emitted from the laser light source in accordance with the modulation signal, and conversion into recording laser light; An objective lens for irradiating a recording laser beam onto the optical disc to form a pit row;
An information recording apparatus comprising: means for generating a gate signal synchronized with a data block unit of the modulation signal; and means for changing the duty of the modulation signal in accordance with the gate signal.

(18) a laser light source, means for converting digital data into a modulation signal, means for intensity-modulating the laser light emitted from the laser light source in accordance with the modulation signal, and converting the laser light into recording laser light; An objective lens for irradiating a recording laser beam onto the optical disc to form a pit row; a means for generating a gate signal synchronized with a data block unit of the modulation signal; An information recording device comprising: means for changing a width.

On the other hand, the optical disk of the present invention, an optical information track is formed by arranging a plurality of information pits circumferentially
A disc , wherein a singular pit row constituted by arranging a part of the plurality of information pits such that a center line thereof is displaced in a radial direction is periodically formed on the information track in a data block unit of a recording signal, It is characterized by a plurality being intermittently arranged.

[0031] The optical disk of the present invention, an optical information track is formed by arranging a plurality of information pits circumferentially
A disc , wherein a peculiar pit row formed by arranging a part of the plurality of information pits such that a center line thereof wobbles in a radial direction is periodically formed on the information track in a data block unit of a recording signal; It is characterized by a plurality being intermittently arranged.

[0032] The optical disk of the present invention, an optical information track is formed by arranging a plurality of information pits circumferentially
A disc , wherein a singular pit row constituted by arranging a part of the plurality of information pits such that a center line thereof is displaced in a radial direction is periodically formed on the information track in a data block unit of a recording signal, It is characterized by being arranged intermittently and arranged so as to be synchronized with the data block of the recording signal.

Further, the optical disk of the present invention, an optical information track is formed by arranging a plurality of information pits circumferentially
A disc , wherein a peculiar pit row formed by arranging a part of the plurality of information pits such that a center line thereof wobbles in a radial direction is periodically formed on the information track in a data block unit of a recording signal; It is characterized by being arranged intermittently and arranged so as to be synchronized with the data block of the recording signal.

Further, the optical disk reproducing apparatus of the present invention is configured by arranging a part of a large number of information pits which are arranged in a circular shape to form an information track so that the center line thereof is displaced or wobbled in a radial direction. An optical disc in which a plurality of unique pit strings are periodically and intermittently arranged on the information track in data block units of a recording signal is reproduced.
An optical disk reproducing device, an optical pickup for reading the optical disk , a detecting unit for detecting the presence or absence of the unique pit row based on a signal read by the optical pickup, and according to a detection result of the detecting unit, Determining means for determining whether or not the optical disc being reproduced is a copied one.

Further, the optical disk reproducing apparatus of the present invention is configured by arranging a part of a large number of information pits which are arranged in a circular shape to form an information track so that the center line thereof is displaced or wobbled in a radial direction. An optical disc in which a plurality of unique pit strings are periodically and intermittently arranged on the information track in data block units of a recording signal is reproduced.
An optical disk reproducing device, an optical pickup for reading the optical disk , a detecting means for detecting the unique pit string based on a signal read by the optical pickup, and counting the number of detections detected by the detecting means, If this count is equal to or greater than a predetermined number within a predetermined period,
Determining means for determining that the optical disk being reproduced is not a copied one.

Further, the optical disk reproducing apparatus of the present invention is constructed by arranging a part of a large number of information pits which are arranged in a circular shape to form an information track so that the center line thereof is displaced or wobbled in a radial direction. An optical disc in which a plurality of unique pit strings are periodically and intermittently arranged on the information track in data block units of a recording signal is reproduced.
An optical disc reproducing apparatus, comprising: an optical pickup for reading the optical disc ; a detection unit for detecting a tracking error based on a signal read by the optical pickup; and a detection signal from the detection unit and a reference signal. Comparing means for counting the number of outputs synchronized with the data block of the read signal out of the outputs of the comparing means, and if the counted number is equal to or more than a predetermined number within a predetermined period, Determining means for determining that the optical disk has not been copied.

In the optical disk recording method according to the present invention, a part of a large number of information pits which are arranged in a circular shape to form an information track is arranged such that the center line thereof is displaced or wobbled in a radial direction. An optical disc recording method for producing an optical disc in which a plurality of unique pit arrays are arranged, wherein the optical modulation of a laser beam emitted from a light source with an information signal to be recorded is performed. Deflecting the laser light periodically and intermittently in the radial direction of the optical disc in units of data blocks of a recording signal to form the plurality of unique pit rows on the information track. .

[0038]

According to the present invention, a specific pit row is formed in a pit conforming to a normal standard on an optical disc. The unique pit row has a shape or arrangement different from that of the normal pit, and is provided on the optical disc in relation to the data block of the modulation signal recorded as the normal pit row. In the singular pit row portion, a wobble signal is obtained from the tracking error signal or the light amount signal changes.
Utilizing this, the detection is performed. Even if a regular optical disk including a unique pit is copied, the copy is not performed up to the unique pit. Therefore, an illegal copy disk can be determined by detecting the unique pit.

[0039]

[Example] Hereinafter, the present onset Akira embodiment will be described in detail with reference to the accompanying drawings.

<First Embodiment> First, a first embodiment of the present invention will be described with reference to FIGS. First , the pit shape of the disk in this embodiment will be described with reference to FIGS.

FIG. 1A shows the wobble pit shape of the disk in this embodiment, and FIG. 1B shows a tracking error when reading the wobble pit. In these figures, the left part has a normal pit arrangement similar to that of a CD or the like, and the pit center line coincides with the track center line. On the other hand, the center line of the singular pit row on the right side is shifted from the center line, and the pit center is wobbled (meandering) when viewed from the center of the virtual track.

When such a pit row is subjected to tracking by a pickup having beam spots S1 to S3 to determine the error, the reflected light amounts of the beam spots S1 and S3 become substantially equal in the left part, and the tracking error The signal becomes "0". On the other hand, in the right portion, the reflected light amounts of the beam spots S1 and S3 become unbalanced, and the tracking error signal increases in proportion to the deviation from the virtual track center line. Therefore, when a portion where the pit row is wobbled is reproduced, a wobble signal is superimposed on the tracking error signal to obtain the tracking error signal.

In this embodiment, such a wobble signal is periodically and intermittently recorded on a predetermined track in data block units. Therefore, if a wobble signal is obtained intermittently in synchronization with the data block unit of the recording signal, the disc is determined to be a legitimate disc. In other cases, the disc is determined to be an unauthorized disc, and as a result, copying is prevented. It has become.

The tracking error is excessively increased by the wobbled pit row as described above, and a seek error does not occur, or a data error cannot be caused without reading out the data of the pit row. It is necessary to set the deviation amount within. For example, the shift width of the pit center is set to be within about 2% of the track pitch and within about 5% of the radial width of the pit.

FIG. 2 shows an arrangement example of the wobbled singular pit row. As shown in the figure, the peculiar pit strings are intermittently arranged in a burst form as shown in FIG. 4D with a logical unit of a predetermined track, for example, a frame shown in FIG. . In the example shown in the figure, a unique pit row is arranged in an even frame, and a normal pit row is arranged in an odd frame. The tracking error due to the wobble signal of the peculiar pit row is as shown in FIG.

Next, the frequency of the wobble signal based on the unique pit string will be described with reference to FIG. The spectrum of the tracking error signal when a normal disc is reproduced by a three-beam pickup is represented by a graph GA.
There is a recording signal component as shown by. This recording signal component increases and decreases in a cycle determined by the distance between the side spots S1 and S2 shown in FIG. At the frequencies of points A and C in the figure, which correspond to the peaks of the recording signal components, the recording signal components become noise, and a good C / N cannot be obtained for the wobble signal (see GB and GC).

However, at the frequency of the point B corresponding to the valley of the recording signal component, such noise is reduced, and a good C / N can be obtained for the wobble signal (see GD). Therefore, if the frequency of the valley of the recording signal component such as point B is selected as the frequency of the wobble signal,
Very effective.

In a portion where data such as lead-in and lead-out on the disk is "0", the recording signal component is reduced as shown by a dotted line GE in FIG. Can be obtained.
Accordingly, if the unique pit train that generates the wobble signal is arranged in a portion where the data such as lead-in and lead-out is “0”, the same great effect can be obtained.

Reproducing Apparatus Next, an embodiment of the disc reproducing apparatus will be described with reference to FIGS. FIG. 4 shows a block diagram of a main part of a reproducing apparatus for a disk including the above-described unique pit string. Pickup 3 from disk 30
2 is supplied to the RF processing circuit 34 and the servo processing circuit 36. The RF signal output from the RF processing circuit 34 is supplied to a signal processing circuit 38, and the obtained subcode and frame information are supplied to a microcomputer 40.

On the other hand, the servo processing circuit 36
In the case of a D-ROM reproducing device, a tracking error signal detection unit is provided, and a tracking error is detected as an error signal. This tracking error signal is supplied to a burst tracking error detection circuit 42, where the burst signal is extracted and supplied to the microcomputer 40 as a digital signal.

FIG. 5 shows an example of the burst tracking error detecting circuit 42, which includes a band-pass filter 42A for extracting only the burst signal frequency, a rectifying circuit 42B for converting the burst signal into a direct current, and a reference output circuit 42.
C and a comparator 42D. The characteristics of the bandpass filter 42A are as shown by GF in FIG. 3, and the center frequency substantially coincides with the point B in order to efficiently extract only the wobble signal. In addition, it does not need to be a trapezoid like GF, and may be a single-peak notch type.

Next, the operation of the burst tracking error detection circuit 42 will be described with reference to FIG. The tracking error signal generated by the burst of the peculiar pit string existing in the even-numbered frame in the frame shown in FIG. 6A is output from the servo processing circuit 36 in FIG. It is supplied to the tracking error detection circuit 42. Then, the bandpass filter 42A extracts only a predetermined frequency component from the input error signal. As a result, the noise component is removed as shown in FIG.

This signal is rectified by the rectifier circuit 42B, and the envelope is taken out as shown in FIG. 4D and becomes the inverted input of the comparator 42D. On the other hand, a non-inverting input of the comparator 42D is provided with a reference output circuit 42C.
Supplies a reference signal VTH (see FIG. 3D). In the comparator 42D, both inputs are compared, and the envelope is digitized as shown in FIG.
In the microcomputer 40, when a frame is read from the disk 30, this burst tracking error signal is referred to. As shown in FIG. 6 (E), a logical value "H" indicates a burst, and a logical value "L" indicates no burst. Is recognized.

FIG. 7 shows the timing at which the microcomputer 40 recognizes the wobble signal. In this example, there is no wobble signal in the odd frames of the disc 30 and the wobble signal is recorded in the even frames, and the intermittent arrangement is such that the wobble signal appears alternately for each frame. 6A shows a frame, FIG. 6B shows a tracking error signal, and FIG. 6C shows a burst tracking error signal shown in FIG.

The microcomputer 40 to which the frame number shown in FIG. 7D is supplied from the signal processing circuit 38 in FIG. 4 first obtains the frame number at the timing indicated by QA in FIG. The frame number is recognized at the timing shown. After a predetermined delay, the burst tracking error signal is read at the timing indicated by QC. If the frame is an even-numbered frame, the burst tracking error signal is counted. If the frame is an odd-numbered frame, the counting is performed without the wobble signal. Note that Q in FIG.
During periods other than A, QB, and QC, other appropriate processes are executed.

Next, the operation of identifying an unauthorized disk according to the present embodiment will be described with reference to FIG. First, when a power supply (not shown) is turned on, it is checked whether or not the disk 30 is set (step S1), and then the TOC area is read (step S2). Then, the DA such as a CD performs normal audio reproduction (step S
4). However, in the case of a CD-ROM, seeking is performed on a track on which a wobble of a predetermined specific pit row is formed (step S5), and after a counter is cleared (step S5).
6) The frame and the burst tracking error signal are read (steps S7, S8).

In the microcomputer 40, if there is a burst in the even-numbered frame, the even counter is incremented by one.
If not, leave as it is (steps S9, S10, S1
1). Similarly, if there is no burst in the odd-numbered frame, the odd counter is incremented by one, and if there is no burst, it is left as it is (steps S9, S12, S13). The above operation is repeatedly performed until a predetermined frame is read (step S1).
4).

As a result, if both the even counter and the odd counter are equal to or more than the predetermined number (steps S15 and S1).
6Y), and recognize / determine as a normal disk (step S)
17) The process proceeds to a normal ROM reproduction operation such as game reproduction (step S21). If one of the counters is not equal to or more than the predetermined number (N in steps S15 and S16), the disk is recognized and determined as an invalid disk (step S18), and measures such as stopping and ejecting the disk are taken (steps S19 and S16).
20).

Note that this algorithm corresponds to step S5
As shown in the above, the case where the track in which the burst-like wobbles are intermittently arranged is only one area in the disk shape, and further by providing such a track in a plurality of areas of the disk, the scratches and dirt on the disk can be improved. For example, the probability of incorrectly recognizing an unauthorized copy disk as a legitimate disk can be reduced, and a more accurate disk check can be performed.

Also, in the example of FIG. 8, it is assumed that the wobbled tracks are stored in the playback device in advance. However, there are a plurality of wobbled tracks on the disk, and an area in which the addresses thereof are in a table is determined in advance. Alternatively, the playback device may be configured to store only the address of the area of the table. In this case, the operation of the reproducing apparatus is to first seek to a track in the stored table area, read the table there, access a plurality of wobbled tracks written therein, and detect the wobble. With this method, if the table cannot be decrypted, the copycode detection operation becomes difficult to understand,
Analysis for copying can be made more difficult.

As described above, according to the reproducing apparatus of this embodiment, when copying a disc containing peculiar pits and trying to read it with a normal CD-ROM drive or the like, the data is modified. Not a CD
-It can be copied correctly to a WO disk or the like without error. Also, it can be used as a master to produce a large number of copy discs.

However, even if data can be copied, the wobbled singular pit structure cannot be copied. Therefore, when applied to the present reproducing apparatus, no tracking error is detected at a predetermined address, and the reproducing operation is not performed. In this way, the disk on which the illegal copy has been made is effectively eliminated (the same applies to the following embodiments). As described above, according to the disk of this embodiment, since the wobble is provided in synchronization with the data block, the wobble signal can be easily and accurately detected, and the wobble is one.
Since they are provided not only in pulses but also in bursts, erroneous detection due to scratches or dirt can be prevented. Also,
Since the burst wobble is provided intermittently every other frame in synchronization with the data block,
Compared with the case where the wobble signal is provided so as to be continuously obtained, it is difficult to improve a reproducing apparatus intended for illegal copying, and copy prevention is more effectively performed.

Recording Apparatus Next, a recording apparatus (master disc cutting apparatus) for obtaining the disk of this embodiment will be described with reference to FIG. As shown in the figure, for example, digital data for a game program is input to an EFM encoder 50, converted into an EFM signal, and output. The EFM signal is input to the optical modulator driver 52 on one side, and is output as an optical modulator drive signal. This optical modulator drive signal is input to the optical modulator 54.

On the other hand, the EFM signal is
, Where the subcode signal included in the EFM signal is extracted and output. This subcode signal is C
It is input to the PU 58 and the gate signal generator 60. CPU
At 58, the address information included in the subcode signal is constantly monitored, and a control signal (see FIG. 2B) is generated and output when a predetermined address at which the protection code is to be recorded is reached. This control signal is input to the gate signal generator 60.

When the gate signal generator 60 receives a control signal from the CPU 58, it generates a gate signal (see FIG. 2C) synchronized with the subcode frame. This gate signal corresponds to a protect code. For example, when the sub-code frame is an odd-numbered frame, the logical value is "L", and when the sub-code frame is an even-numbered frame, the logical value is "H". Of course, the reverse logical value relationship may be used. Such a gate signal is input to an FG (frequency generator) 62.

When the gate signal is "H", the FG 62
That is, a sine wave of a predetermined frequency is generated in the case of an even frame, and no waveform is generated when the gate signal is "L", that is, in the case of an odd frame. Therefore, FG62
Is a burst-like wobble signal synchronized with the subcode frame (see FIG. 2D). This wobble signal is input to the optical deflector driver 64 and is input to the optical deflector 66 as an optical deflector drive signal.

On the other hand, the laser beam La is continuously irradiated from the laser oscillator 68 onto the optical modulator 54, and the laser beam a first passes through the optical modulator 54. At this time, the laser beam Lb undergoes signal modulation corresponding to the optical modulator drive signal, and becomes a laser beam Lb in which the intensity of the laser beam La changes over time, and passes through the optical deflector 66. Then, the laser light Lb becomes the laser light Lc deflected in accordance with the optical deflector drive signal. This laser light Lc is
The light is radiated on the master 72 as a minute spot. The minute spot is deflected in the radial direction on the master 72 by the optical deflector 66, and a wobbled pit pattern as shown in FIG. 1A is formed. In this way, a disk suitable for copy protection including the wobble of the peculiar pit row is obtained.

As described above, the recording apparatus of this embodiment does not record the protect code in the data to be recorded on the disk, but records a unique pit string having a different shape from the regular pits at the time of cutting the master. This is a method of arranging and recording in accordance with the signal data block unit. For this reason, except for the original disk manufacturer, a large amount of capital investment is required even if the duplication is performed from the cutting process, so that the duplication is virtually impossible, and a very powerful illegal copy prevention can be realized. The same applies to the embodiment of the recording apparatus described above.)

Note that Japanese Patent Application Laid-Open No. 2-87344 discloses that
A recording medium in which an address is written in a wobble portion, and a recording device and a reproducing device thereof are disclosed. However, in this method, data must be read one bit at a time, as shown in FIGS. For this reason, a synchronous circuit is required, and the data decoding timing becomes strict, so that the circuit configuration becomes complicated as a whole.
Further, since the data recording density is high, the data reading error rate tends to be high.

On the other hand, this embodiment can be realized by a relatively simple circuit as described above, and is advantageous in cost of the reproducing apparatus. In addition, since the data format has a relatively long burst time, the data recording density is significantly low, and even if there are some disk defects, decoding can be performed without any inconvenience. That is, according to the present embodiment, it is possible to considerably tolerate a defect in manufacturing the disk, and as a result, it is possible to improve the yield in manufacturing the disk and reduce the manufacturing cost. Further, as the disk is used, the surface of the disk may become dirty or scratched. However, since the data recording density of the burst portion is low, the disk portion can be made stronger.

< Reference Example 1 > Disc Next, although not related to the present invention, it is useful for understanding the present invention.
Reference Example 1 will be described with reference to FIGS. This reference example 1 uses the R output from the pickup.
It is to use the symmetry of the F signal (symmetry).

First, referring to FIGS. 10 to 12,
The pit shape of the disc will be described. In FIG. 10, (B) is a pit row having a duty of 50%. When this pit string is reproduced, R as shown in FIG.
An F signal waveform is obtained. The RF signal is vertically symmetrical, and the slice level passing through the center of a portion called a diamond-shaped eye indicated by oblique lines in FIG.

The example in FIG. 10A is a pit row formed by the recording signal having been subjected to duty correction.
The length before and after each pit is shortened by a as compared with the pit row of (B). When such a pit row is reproduced, the vertical symmetry of the RF signal is broken, and the slice level moves upward in FIG. Similarly, FIG.
The example of 0 (C) is also a pit row formed by the recording signal having been subjected to the duty correction, and the length before and after each pit is longer by b than the pit row of (B). . When such a pit train is reproduced, the slice level of the RF signal moves downward in FIG. As described above, the slice level fluctuates up and down in accordance with the change in the duty of the pit, and the slice level meanders.

FIG. 12 shows another pit mode in which the slice level changes. As shown in FIG. 3A, in this example, a pit width that is larger or smaller than the normal pit width in the radial direction of the disk is used as a unique pit row. The RF signal waveform of each pit row is as shown in FIG. That is, in the case of a normal pit, the waveform is shown by the graph GH, and the slice center is SL1.
However, in the case of a thick pit, the reflection is large and the modulation is large, the RF signal is as shown in the graph GI, and the slice level is reduced to SL2. In the case of thin pits, the modulation level decreases and the slice level increases as shown by the graph GJ. Even in such a pit mode, when the unique pits having different widths are alternately present, the slice level appears to meander as seen from the slice level of the normal pit.

Next, with reference to FIGS. 13 to 15, a description will be given of a reference example of a reproducing apparatus that checks for illegal copying by utilizing the symmetry of the RF signal waveform described above. FIG. 13 shows the configuration, in which an RF symmetry fluctuation detection circuit 80 is provided instead of the burst tracking error detection circuit 42 shown in FIG. Other blocks are the same as in FIG. RF symmetry change detection circuit 80
Is for receiving an RF signal from the RF processing circuit 34, detecting a change in slice-level symmetry, and supplying a detection signal to the microcomputer 40.

FIG. 14 shows an RF symmetry change detection circuit 80.
Of the auto-slice circuit 80A,
A reference output circuit 80B, a comparison circuit 80C, and a monostable multivibrator circuit 80D are included. A general RF signal is an analog waveform, and when converting the analog signal to a logic level, it is necessary to adapt the slice level to the center of the RF signal waveform even if the RF signal waveform becomes vertically asymmetric due to the pit aspect. In order to obtain such an adapted slice level, an auto slice circuit 80A is used.

Next, the operation of the present apparatus will be described with reference to FIG. Now, assuming that the unique pit row shown in FIG. 10 or FIG.
The eye of the F signal waveform fluctuates up and down as shown in FIG. 11, and this is detected by the auto slice circuit 80A. FIG. 15A shows an example of such a slice level variation.

In the comparison circuit 80C, the slice level is compared with the slice level limits SLL1 and SLL2 (see FIG. 15A) output from the reference output circuit 80B. This allows the comparison circuit 80C to output the signal from FIG.
A slice level variation signal as shown in FIG. This signal is a monostable multivibrator circuit 80D
, Where a constant time constant is given as shown in FIG. Since the slice level changes relatively quickly, a signal having a width that can be recognized by the microcomputer 40 is provided by giving a time constant.

The basic operation of recording and detecting a specific pit on a predetermined track in the disk is the same as that of the above-described embodiment, so that the specific pit detection algorithm is basically the same as that of FIG. It is. In the case of the first embodiment, step S8 in the figure may be referred to as "detection of RF signal slice level fluctuation". FIG. 7 also shows the timing of detecting a unique pit in the microcomputer 40.
This is the same as (E), and the “detection of slice level fluctuation of the RF signal waveform” may be performed at the timing of “tracking error detection” indicated by QC.

Auto slice circuit 80A shown in FIG.
For example, there is an IC “TC9263F” manufactured by Toshiba Corporation. According to this, the slice level is output to the outside, and when the RF signal waveform becomes asymmetric, an analog signal indicating the slice level corresponding thereto is obtained.

[0081] Thus, according to the reproducing apparatus of the present embodiment, until the asymmetric waveform similarly RF signal as in the Example 1 can not be copied. For this reason, the copied disk does not change in slice level, so that the copied disk can be excluded in the same manner.

Recording Apparatus Next, with reference to FIGS. 16 and 17, a description will be given of a recording apparatus (a master cutting machine) for a disk containing the above-described unique pits. As shown in FIG.
Digital data such as programs is stored in EFM encoder 5.
0, where it is converted to an EFM signal and input to the subcode reader 56 and the duty corrector 82, respectively. In the subcode reader 56, a subcode signal included in the EFM signal is extracted.
Each is input to the gate signal generator 60.

The CPU 58 constantly monitors the address information contained in the subcode signal, and generates a control signal when the address reaches a predetermined address where the protection code is to be recorded, and inputs the control signal to the gate signal generator 60. You. The gate signal generator 60 generates and outputs a gate signal synchronized with the subcode frame according to a control signal from the CPU 58. FIG. 17 shows this state.
(A) shows the frame number, (B) shows the control signal,
(C) is a gate signal.

This gate signal corresponds to a protect code. For example, when the sub-code frame is an odd-numbered frame, the logical value is "L", and when the sub-code frame is an even-numbered frame, it is "H".
And so on. Of course, the opposite logical value may be used. The gate signal is input to the duty corrector 82. When the gate signal is "H", that is, in the case of an even frame, the duty corrector 82 performs a predetermined duty correction on the EFM signal. However, when the gate signal is "L", that is, when the frame is an odd frame, the duty correction is not performed. The recording signal corrected in this way is supplied from the duty corrector 82 to the output modulator driver 52. An optical modulator drive signal is input from the output modulator driver 52 to the optical modulator 54.

On the other hand, laser light La is continuously irradiated from the laser oscillator 68 onto the optical modulator 54, and the laser light La is modulated by the optical modulator drive signal when passing through the optical modulator 54. . As a result, laser light Ld whose intensity has changed with time can be obtained. The laser beam Ld is irradiated as a minute spot on the master 72 by the objective lens 70, and pit patterns having different duties as shown in FIGS. 10 and 17D are formed.

As shown in FIG. 17E, the slice level of the reproduction RF signal of such a disk is as shown in FIG.
Fluctuates in synchronization with the block number shown in FIG. If such a slice level fluctuation signal is detected as shown in FIG. 3F, it is determined that the disk is a legitimate disk, and in other cases, it is determined that the disk is an unauthorized disk, which can contribute to prevention of copying.

< Reference Example 2 > Next, reference example 2 will be described with reference to FIGS. The reference example 2, Ri Reference Example der to utilize variations in the reflected light amount of the disc, its is not relevant to the present invention
It is to help understanding.

[0088] The disk 18 is another example of the pit shape is shown in this embodiment. The pits in the center section FR in FIG.
The pits have a regular width on this disk, and the reproduced waveform is as shown in FIG. In this waveform, the reflectance is high at the top and low at the bottom.

The width of the singular pit in the section FS in FIG. 9A is wider than that of the normal pit in the section FR by 2a. The reproduced waveform in this case has a wider amplitude but a lower overall reflectance, as shown in FIG. Similarly, the singular pit in the section FT in FIG. 3A is smaller in width by 2b than the normal pit in the section FR. In the reproduced waveform in this case, as shown in FIG. 9B, the overall reflectance increases but the amplitude decreases.

Reproducing Apparatus Next, with reference to FIGS. 19 and 20, a description will be given of a reference example of a reproducing apparatus for checking a disc by using the above-described variation in the amount of reflected light due to the unique pit. FIG. 19 shows the configuration, in which a light quantity fluctuation detection circuit 90 is provided instead of the burst tracking error detection circuit 42 shown in FIG. Other blocks are the same as in FIG.

The light quantity fluctuation detection circuit 90 has the configuration shown in FIG. 20, and adds the light quantity signal supplied from the servo processing circuit 36 by an adder 90A. Specifically, the addition of the light amount signals of the photodetectors E and F E + F (corresponding to the addition of the sub-beams) or the photodetectors A, B,
Addition A + B + C + D of the C and D light quantity signals (corresponding to full addition of the main beam 4-split sensor) is performed, and these become light quantity fluctuation signals. This light quantity fluctuation signal is compared with a reference value VT output from a reference output circuit 90C in a comparator 90B, and a light quantity fluctuation signal exceeding the reference value is supplied to the microcomputer 40.

Since the basic operation of recording and detecting a specific pit on a predetermined track in the disk is the same as that of the above embodiment, the specific pit detection algorithm is basically the same as that of FIG. It is. In the case of the reference example 2 , step S8 in FIG.
And it is sufficient. Further, the timing of detecting a specific pit in the microcomputer 40 is the same as that in FIG. 7E, and the “reflection light amount fluctuation detection” may be performed at the timing of “tracking error detection” indicated by QC.

[0093] Thus, the reproducing apparatus of the present embodiment is a method of operating a disk reflected light, if reasonably short specificity pits is corrected in the CD-WO disc is copied without issuing an error . However, since the disk cannot be copied up to the pit shape, a disk in which the reflected light amount does not fluctuate is eliminated in the same manner as in the above embodiment. Also, if the size of the unique pit is increased, a data error occurs in the CD-WO disc reproducing device and the reproducing operation stops, or the area cannot be copied. Therefore, similarly copied disks are excluded.

Recording Apparatus Next, with reference to FIGS. 21 and 22, a description will be given of a recording apparatus (a master cutting machine) for a disk including the above-described unique pits. As shown in FIG.
Digital data such as programs is stored in EFM encoder 5.
0, where it is converted to an EFM signal, input to the first optical modulator driver 92, and output as a first optical modulator drive signal. This first optical modulator drive signal is:
The signal is input to the first optical modulator 94.

On the other hand, the EFM signal is
6, where the sub-code signal included in the EFM signal is extracted, and the CPU 58 and the gate signal generator 60
Respectively. The CPU 58 constantly monitors the address information included in the subcode signal, and generates and outputs a control signal when a predetermined address at which the protection code is to be recorded is reached. This control signal is input to the gate signal generator 60. Gate signal generator 60
When a control signal is input from the CPU 58, a gate signal synchronized with the subcode frame is generated and output. FIG. 22 shows the situation, and FIG.
Is a frame number, (B) is a control signal, and (C) is a gate signal.

This gate signal corresponds to a protect code, and has a logical value corresponding to an odd or even number of a frame. The gate signal is input to the second optical modulator driver 96, and is input to the second optical modulator 98 as a second optical modulator drive signal.

On the other hand, the laser light La is continuously radiated from the laser oscillator 68 to the first optical modulator 94.
When the laser light La passes through the first optical modulator 94, the first
Is modulated by the optical modulator drive signal of As a result, laser light Le whose intensity has changed with time can be obtained.
The laser light Le is modulated by the second light modulator drive signal when passing through the second light modulator 98, and becomes a laser light Lf. The laser beam Lf is irradiated as a minute spot on the master 72 by the objective lens 70, and FIG.
Pit patterns having different widths as shown in FIG.

As described above, when pit rows having different widths are arranged as shown in FIG. 22D in accordance with the gate signals in FIG. 20C synchronized with the block numbers in FIG. The signal is as shown in FIG. 9E, and the envelope of the reproduced waveform fluctuates up and down in synchronization with the block number. If the fluctuation signal of the envelope is detected as shown in FIG. 7F, the disk is determined to be a legitimate disk, otherwise, it is determined to be a fraudulent disk, which can contribute to the prevention of copying as in the above-described embodiment. .

[0099] <Example 2> Next, Embodiment 2 of the present invention will be described with reference to FIGS. 23 to 26. FIG. 23A shows a pit shape of the disk in the second embodiment, and FIG. 23B shows a tracking error signal obtained when the pit is read out. In FIG. 9A, the pits in the left area conform to the normal standard, and the pit center line coincides with the track center line. On the other hand, some pits in the region of the right singular pit row have a shape whose width is increased on one side (the lower side in the figure in this example) with respect to the track center line.

The laser spots S1 to S3 of the three-beam method pickup are applied to such a pit row, and two spots S which are arranged offset in the radial direction.
By subtracting the reflected light amounts of 1, S3, a tracking error signal is obtained as is well known. Figure (A)
In the case of the pit row shown in FIG. 7, in the left area, the pit shapes are symmetrical with respect to the track center line, so that the reflected light amounts of the spots S1 and S3 are almost equal. Therefore, the tracking error signal becomes almost “0”.

On the other hand, in the area of the right singular pit row on the right side, the pit shape is asymmetric with respect to the track center line, so that the reflected light amounts of the two spots S1 and S3 become unbalanced, and the tracking error The signal increases, and a signal waveform as shown on the right side of FIG. By periodically arranging such asymmetric pits and normal pits in the unique pit row,
A burst-like tracking error signal is obtained.

In the present embodiment, a unique pit train for generating such a burst-like tracking error signal is periodically and intermittently recorded on a predetermined track in data block units. Therefore, if a burst signal is obtained intermittently in synchronization with the data block unit of the recording signal, the disc is determined to be a legitimate disc. In other cases, the disc is determined to be an unauthorized disc, and as a result, copying is prevented. It has become.

FIG. 24 shows an example of an arrangement of a peculiar pit row in which the tracking error increases in a burst manner.
As shown in the figure, the peculiar pit string is a logical unit of a predetermined track, for example, a frame shown in FIG.
They are intermittently arranged as shown in FIG. In the example shown in the figure, a unique pit row is arranged in an even frame, and a normal pit row is arranged in an odd frame. The tracking error signal due to the unique pit train is shown in FIG.
It becomes as shown in. Reproducing device This is the same as in the first embodiment.

Recording Apparatus Next, a recording apparatus (master disc cutting apparatus) for obtaining the disc of this embodiment will be described with reference to FIGS. As shown in FIG. 26, digital data such as a game program is input to an EFM encoder 50, where it is converted into an EFM signal, and is sent to a subcode reader 56, a unique pit signal generator 100, and a light modulation driver 92, respectively. Is entered. Optical modulator driver 92
Is input to the optical modulator 94.

The sub-code reader 56 extracts a sub-code signal included in the EFM signal.
8, input to the gate signal generator 60, respectively. CP
In U58, the address information included in the subcode signal is constantly monitored, and when a predetermined address at which the protection code is to be recorded is reached, a control signal is generated and input to the gate signal generator 60. Gate signal generator 60
Then, according to the control signal from the CPU 58, the sub-code
A gate signal synchronized with the frame is generated and output. FIG.
FIG. 4A shows the state, FIG. 4A shows a frame number, FIG. 4B shows a control signal, and FIG. 4C shows a gate signal.

This gate signal corresponds to a protection code. For example, when the sub-code frame is an odd-numbered frame, the logical value is "L", and when the sub-code frame is an even-numbered frame, it is "H".
And so on. Of course, the reverse logic may be used. The gate signal is input to the unique pit signal generator 100. In the unique pit signal generator 100, when the gate signal is “H”, that is, in the case of an even frame, the EF
Part of the M signal is extracted and output as shown in FIG. However, when the gate signal is "L", that is, in the case of an odd frame, no signal is output. A part of the EFM signal output in this way corresponds to a unique pit. Such a unique pit signal is transmitted to the optical modulator driver 9.
6. An optical modulator drive signal is input from the optical modulator driver 96 to the optical modulator 98.

On the other hand, a laser beam La is continuously emitted from the laser oscillator 68 and the beam splitter 10
The light is divided into laser light Lg and laser light Lh by 2.
The laser beam Lg passes through the optical modulator 94, and at this time,
The signal beam is modulated according to the optical modulator drive signal shown in (B), and becomes a recording beam Li in which the intensity of the laser light changes with time. Similarly, the laser beam Lh passes through the optical modulator 98, undergoes signal modulation corresponding to the optical modulator drive signal shown in FIG. 25C, and becomes a recording beam Lj.

The recording beam Li and the recording beam Lj are added by the polarization beam splitter 104, and illuminated as a minute spot on the master 72 by the objective lens 70. As shown in FIG. 25A, the positional relationship between the spots of the recording beam Li and the recording beam Lj on the master is offset by optical adjustment. Recording beam L
The spot center of i corresponds to the track center line, and the pit PA is usually formed only by the recording beam Li. Unique pit P
B is formed by overlapping the recording beam Li and the recording beam Lj.

The tracking error signal of such a disk increases in a burst in synchronization with the block number shown in FIG. If such a tracking error fluctuation is detected as shown in FIG. 2F, the disc is determined to be a legitimate disc, and otherwise, it is determined to be a fraudulent disc, and copy prevention can be realized.

[0110] <Example 3> Next, Embodiment 3 of the present invention will be described with reference to FIGS. 27 to 29. FIG. 27A shows the pit shape of the disk in the third embodiment, and FIG. 27B shows a tracking error signal obtained when the disk is read. In FIG. 9A, the pits in the left area conform to the normal standard, and the pit center line coincides with the track center line. On the other hand, the pits in the area of the right singular pit row have the same pit shape as normal pits, but are wobbled with respect to the track center line.

The laser spots S1 to S3 of the three-beam method are applied to such a pit row, and two spots S which are arranged offset in the radial direction.
By subtracting the reflected light amounts of 1, S3, a tracking error signal is obtained as is well known. Figure (A)
In the area on the left side of the figure, the tracking error signal is almost "0" as shown in FIG.

On the other hand, in the area of the singular pit row on the right side, the pit shape is displaced with respect to the track center line, so that the reflected light amounts of the two spots S1 and S3 become unbalanced, and the tracking error signal is generated. Increases,
A burst-like signal waveform as shown on the right side of FIG.

In the present embodiment, a peculiar pit sequence for generating such a burst-like tracking error signal is recorded on a predetermined track periodically and intermittently in data block units. Therefore, if a burst signal is obtained intermittently in synchronization with the data block unit of the recording signal, the disc is determined to be a legitimate disc. In other cases, the disc is determined to be an unauthorized disc, and as a result, copying is prevented. It has become.

FIG. 28 shows an example of the arrangement of a specific pit row in which the tracking error increases in a burst.
As shown in the figure, the peculiar pit string is a logical unit of a predetermined track, for example, a frame shown in FIG.
They are intermittently arranged as shown in FIG. In the example shown in the figure, a unique pit row is arranged in an even frame, and a normal pit row is arranged in an odd frame. The tracking error signal due to the unique pit train is shown in FIG.
It becomes as shown in. Reproducing device This is the same as in the first embodiment.

Recording Apparatus Next, a recording apparatus (master disc cutting apparatus) for obtaining the disc of this embodiment will be described with reference to FIGS. 27 to 29. As shown in FIG. 29, digital data such as a game program is input to an EFM encoder 50, where it is converted into an EFM signal, and is sent to a subcode reader 56, a wobble signal generator 110, and an optical modulator driver 52, respectively. Is entered. Optical modulator driver 52
Is input to the optical modulator 54.

In the sub code reader 56, a sub code signal included in the EFM signal is extracted.
8, input to the gate signal generator 60, respectively. CP
In U58, the address information included in the subcode signal is constantly monitored, and when a predetermined address at which the protection code is to be recorded is reached, a control signal is generated and input to the gate signal generator 60. Gate signal generator 60
Then, according to the control signal from the CPU 58, the sub-code
A gate signal synchronized with the frame is generated and output. FIG.
8A and 8B show the situation, wherein FIG. 8A shows a frame number, FIG. 8B shows a control signal, and FIG. 8C shows a gate signal.

This gate signal corresponds to a protection code. For example, when the sub-code frame is an odd-numbered frame, the logical value is "L", and when the sub-code frame is an even-numbered frame, it is "H".
And so on. Of course, the reverse logic may be used. The gate signal is input to the wobble signal generator 110. In the wobble signal generator 110, when the gate signal is “H”, that is, in the case of an even frame, the EFM
A wobble signal corresponding to the signal as shown in FIG. 27C is output. However, when the gate signal is "L", that is, in the case of an odd frame, no signal is output. The wobble signal thus output is supplied to the optical deflector driver 64. An optical deflector drive signal is input from the optical deflector driver 64 to the optical deflector 66.

On the other hand, laser light La is continuously emitted from laser oscillator 68 and passes through optical modulator 54. At this time, the laser light L that has undergone signal modulation corresponding to the optical modulator drive signal and the intensity of the laser light is temporally changing.
b. The laser beam Lb passes through the optical deflector 66 and
The signal is modulated according to the optical deflector drive signal shown in FIG. The laser beam Lc is irradiated as a minute spot on the master 72 by the objective lens 70, and a pit as shown in FIG. 27A is formed.

The tracking error signal of such a disk becomes a burst in synchronization with the block number shown in FIG. If such a tracking error fluctuation is detected as shown in FIG. 2F, the disc is determined to be a legitimate disc, and otherwise, it is determined to be a fraudulent disc, and copy prevention can be realized.

<Other Embodiments> The present invention is not limited to the above embodiments, but includes, for example, the following. (1) In the above embodiment, the address information where the unique pits are formed is stored in the check device in advance.
The address information of the unique pit may be stored at a predetermined position on the disk, and the check device may first read the predetermined position when setting the disk. This makes it possible to change the address of the unique pit for each type of disc, thereby making it difficult to analyze the copy protection of the disc and improving the effect of preventing unauthorized copying.

[0121] (2) the specific pit tracking error signal specific pits and the light quantity signal of Example 1 obtained are obtained in Reference Example 1, it may be allowed to coexist in a single disc. By doing so, the reliability of copy disk detection can be improved.

(3) According to a general standard for CDs (for example, “JIS X6281” or “IEC908”), errors must not be output beyond a certain range. To the extent that it does not violate it,
If the length of the pit, the degree of wobble, the symmetry of the RF signal, or the amount of reflected RF light are manipulated, no particular inconvenience occurs as a disc even if the special pits are provided. (4) Also, in the field of TV games and the like, it is usually unnecessary for a game disc to be playable on a game machine other than the play game machine. Therefore, there is no need to consider compatibility with a disc used in a personal computer or the like, and there is no practical problem.

(5) In the above embodiment, when a disc is set, it is determined whether or not there is a unique pit, and it is checked whether or not the disc is a copy disc. , May be set as needed.

( 6 ) In the above embodiment, the unique pit row is intermittently arranged in synchronization with the even-numbered frame.
An arrangement related to another frame, for example, an arrangement shown in FIG. First, FIG. 2 (B) shows an intermittent arrangement in the above-mentioned even-numbered frame (FIG. 2).
(D), FIG. 7 (B), FIG. 17 (D), and FIG. 22 (D)). FIG. 9 (C) shows an arrangement in which unique pit rows are intermittently arranged in odd-numbered frames. In any case, by referring to only the least significant bit of the frame number, it is possible to determine whether or not the frame includes the peculiar pit string, so that data transfer to the CPU and processing in the CPU can be simplified. .

FIG. 30 (D) shows a large interval between frames including the peculiar pit strings, and the one shown in the figure is intermittent every two frames. FIG. 9 (E) includes a specific pit row continuously over several frames, and the illustrated one is continuous for two frames. This may be provided intermittently every predetermined number of frames. According to these two examples, it is possible to avoid crosstalk between the peculiar pit rows due to the wobble of the adjacent track, and to improve the detection sensitivity by increasing the wobble amplitude.

FIG. (F) shows a case where a plurality of unique pit rows are provided in one frame. Needless to say, a plurality thereof may be provided intermittently. According to this example, since the detection accuracy is required, there is an advantage that the copy guard is not easily broken. Each of the embodiments shown in (B) to (F) above is an example in which a unique pit string is formed in synchronization with a frame which is a data block. Note that, as shown in FIG. 3G, the length of the wobble and the length of the data block do not need to be the same as long as they are synchronized with the frame. In the illustrated example, the peculiar pit train starts after the start of the frame.

FIG. (I) shows that one frame corresponds to four frames.
In addition to these, a 4-bit code is assigned to each of them, and a portion corresponding to the logical value “H” includes a unique pit string. The bit division is set based on the data synchronization signal shown in FIG. The unique pit formation position is set in advance so that the distance from the data synchronization position to the unique pit row formation position differs for each frame. Although higher detection accuracy is required as compared with the embodiment of (F), there is an advantage that the copy guard is harder to break.

FIG. 29 (J) shows that the delay amount at the start of the peculiar pit train is a1, a2,
This is an example in which a peculiar pit row is formed, for example, the state changes to a3,... and returns to a1 again after a large delay to a5. Also in this example, the unique pit row is synchronized with the frame, and the hardware and software for detection are further complicated. However, there is an advantage that the copy guard is higher and is hardly broken without being analyzed. In each of the examples shown in FIG. 30 described above, the unique pits are formed in relation to the frame. However, an appropriate data block unit other than the frame may be used.

[0129]

According to the onset bright As described above, according to the present invention, a predetermined address of the optical disk, so it was decided to check the existence and form specific pit in relation to the data blocks, unauthorized copying disk Easy In addition, there is an effect that accurate copy protection can be realized by accurate detection.

[Brief description of the drawings]

FIG. 1 is a diagram illustrating a pit shape and a tracking error signal thereof according to a first embodiment of the present invention.

FIG. 2 is a diagram illustrating a relationship between a frame and a unique pit row in the first embodiment.

FIG. 3 is a graph showing a relationship between a wobble signal and noise in the first embodiment.

FIG. 4 is a block diagram illustrating a configuration of a playback device according to the first embodiment.

FIG. 5 is a block diagram illustrating an example of a burst tracking error detection circuit.

FIG. 6 is a signal waveform diagram illustrating an operation of the burst tracking error detection circuit.

FIG. 7 is a timing chart showing burst tracking error detection and recognition.

FIG. 8 is a flowchart showing the operation of the playback device.

FIG. 9 is a block diagram illustrating a configuration of a recording apparatus according to the first embodiment.

FIG. 10 is a diagram showing a unique pit row in Reference Example 1 .

FIG. 11 is a diagram showing a change in a slice level of an RF signal waveform in Reference Example 1 .

FIG. 12 is a diagram showing another shape of the unique pit row in Reference Example 1 .

FIG. 13 is a block diagram illustrating a configuration of a playback device of Reference Example 1 .

FIG. 14 is a block diagram illustrating an example of an RF symmetry change detection circuit.

FIG. 15 is a signal waveform diagram illustrating an operation of the RF symmetry variation detection circuit.

16 is a block diagram showing a configuration of a recording apparatus of Reference Example 1.

FIG. 17 is a diagram illustrating the operation of the recording apparatus of Reference Example 1 .

FIG. 18 is a diagram showing another example of the unique pit row in Reference Example 2 .

FIG. 19 is a block diagram illustrating a configuration of a playback device of Reference Example 2 .

FIG. 20 is a block diagram illustrating an example of a light quantity fluctuation detection circuit.

FIG. 21 is a block diagram illustrating a configuration of a recording apparatus according to a reference example 2 .

FIG. 22 is a diagram illustrating the operation of the recording apparatus of Reference Example 2 .

FIG. 23 is a diagram showing a peculiar pit row in the second embodiment.

FIG. 24 is a diagram showing another unique pit row in the second embodiment.

FIG. 25 is a diagram illustrating an operation of the recording apparatus according to the second embodiment.

FIG. 26 is a block diagram illustrating a configuration of a recording apparatus according to a second embodiment.

FIG. 27 is a diagram showing a peculiar pit row in the third embodiment.

FIG. 28 is a diagram showing another unique pit row in the third embodiment.

FIG. 29 is a block diagram illustrating a configuration of a recording apparatus according to a third embodiment.

FIG. 30 is a diagram showing another embodiment.

[Explanation of symbols]

 10, 30 disk 12 disk set detector 14 disk drive 16, 32 pickup 18 pickup drive 20 head amplifier circuit 22, 38 signal processing circuit 24, 40 microcomputer 26 memory 28 display Apparatus 34 RF processing circuit 36 Servo processing circuit 42 Burst tracking error detection circuit 50 EFM encoder 52, 92, 96 Optical modulator driver 54, 94, 98 Optical modulator 56 Subcode reader 58 CPU 60 ... Gate signal generator 62. Frequency generator 64. Optical deflector driver 66. Optical deflector 68. Laser oscillator 70. Objective lens 72. Master disk 80. RF symmetry variation detection circuit 82. Duty corrector 90. Circuit 100: Unique pit signal generator 102: Bee Splitter 104 ... polarizing beam splitter 110 ... wobble signal generator

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification code FI G11B 7/26 G11B 7/26 19/04 501 19/04 501H 20/10 20/10 H (56) References JP-A-5 -325193 (JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB name) G11B ^7/ 00-7/013 G11B 7/24 561-571 G11B 19/02-19/04 501

Claims (8)

(57) [Claims] 1. An optical disc on which an information track is formed by arranging a large number of information pits in a circular shape, wherein a part of said many information pits is arranged such that a center line thereof is displaced in a radial direction. light des, characterized in that constituted specific pit row is periodic with a data block of a recording signal on said information track is intermittently multiple arrangement
Disk . 2. An optical disk on which an information track is formed by arranging a large number of information pits in a circular shape, wherein a part of said many information pits is arranged such that the center line thereof wobbles in a radial direction. A plurality of unique pit trains are periodically and intermittently arranged on the information track in data block units of a recording signal.
Optical disk . 3. An optical disc on which an information track is formed by arranging a large number of information pits in a circular shape, wherein a part of said many information pits is arranged such that a center line thereof is displaced in a radial direction. light des that constitute specific pit row the information periodically on a track in the data blocks of a recording signal, is intermittently multiple arrangement, and characterized in that it is arranged to synchronize to the data blocks of a recording signal
Disk . 4. An optical disc on which an information track is formed by arranging a large number of information pits in a circular shape, wherein a part of the plurality of information pits is arranged such that a center line thereof wobbles in a radial direction. A plurality of unique pit trains are periodically and intermittently arranged on the information track in a data block unit of a recording signal, and are arranged so as to be synchronized with the data block of the recording signal.
Optical disk . 5. A peculiar pit row constituted by arranging a part of a large number of information pits which are arranged in a circular manner to form an information track so that a center line thereof is displaced or wobbled in a radial direction. A plurality of optical discs are periodically and intermittently arranged on a track in units of data blocks of recording signals.
An optical disk reproducing apparatus for reproducing disk, and an optical pickup for reading said optical disk, and detecting means for detecting the presence of said specific pit array on the basis of the read-out signal by the optical pickup, the detection result of the detecting means According to the light source being reproduced.
Disk optical disk reproducing apparatus, characterized in that it has a discriminating means for discriminating whether or not copied. 6. A peculiar pit row formed by arranging a part of a large number of information pits which are arranged in a circular manner to form an information track so that a center line thereof is displaced or wobbled in a radial direction. A plurality of optical discs are periodically and intermittently arranged on a track in units of data blocks of recording signals.
An optical disk reproducing apparatus for reproducing disk, and an optical pickup for reading said optical disk, a detecting means for detecting said specific pit array on the basis of the signal read by the optical pickup, the number of detection times detected by the detection means counts, if the count number is equal to or more than a predetermined number within a predetermined period of time, the optical disk reproducing apparatus, characterized in that the optical disc being reproduced and a discriminating means for discriminating a that was not copied. 7. A peculiar pit row constituted by arranging a part of a large number of information pits which are arranged in a circular manner to form an information track so that a center line thereof is displaced or wobbled in a radial direction. A plurality of optical discs are periodically and intermittently arranged on a track in units of data blocks of recording signals.
An optical disk reproducing apparatus for reproducing disk, and an optical pickup for reading the optical disk, detection means for detecting a tracking error based on the signal read by the optical pickup, the detection signal and the reference signal from the detection means And a comparing unit that compares the number of outputs synchronized with the data block of the read signal among the outputs of the comparing unit. If the counted number is equal to or more than a predetermined number within a predetermined period, optical disk reproducing apparatus, characterized in that the optical disc being reproduced and a discriminating means for discriminating a that was not copied. 8. A plurality of peculiar pit rows, each of which is constituted by arranging a part of a large number of information pits arranged in a circular manner to form an information track, such that a center line thereof is displaced or wobbled in a radial direction. light di to produce an optical disc to be
A disk recording method, comprising: optically modulating laser light emitted from a light source with an information signal to be recorded; and periodically modulating the light-modulated laser light applied to the optical disk in data block units of a recording signal. optical disc recording method characterized by comprising the step of intermittently deflect in a radial direction of the optical disc, to form a plurality of said specific pit array on the information track.